U.S. patent number 5,482,768 [Application Number 08/242,675] was granted by the patent office on 1996-01-09 for surface-treated substrate and process for its production.
This patent grant is currently assigned to Asahi Glass Company Ltd.. Invention is credited to Fumiaki Gunji, Kazuya Hiratsuka, Takeshi Kawasato, Tsuneo Wakabayashi, Takashige Yoneda.
United States Patent |
5,482,768 |
Kawasato , et al. |
January 9, 1996 |
Surface-treated substrate and process for its production
Abstract
A surface-treated substrate consisting essentially of a
substrate having at least two treated surface layers wherein the
first layer constituting the outermost layer among the treated
surface layers is a layer formed by treating with a treating agent
containing a compound (I) capable of forming a surface having a
contact angle of at least 70.degree. against water, and the second
layer constituting an underlayer in contact with the outermost
layer is a thin film layer of a heat resistant polymer formed by
treating with a treating agent containing a compound (II) capable
of forming a thin film of a heat resistant polymer and fine
particles of a polymer, to form a thin film and heating the thin
film to thermally decompose the fine particles of a polymer.
Inventors: |
Kawasato; Takeshi (Yokohama,
JP), Hiratsuka; Kazuya (Yokohama, JP),
Yoneda; Takashige (Yokohama, JP), Wakabayashi;
Tsuneo (Yokohama, JP), Gunji; Fumiaki (Yokohama,
JP) |
Assignee: |
Asahi Glass Company Ltd.
(Tokyo, JP)
|
Family
ID: |
15178605 |
Appl.
No.: |
08/242,675 |
Filed: |
May 13, 1994 |
Foreign Application Priority Data
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May 14, 1993 [JP] |
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5-136580 |
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Current U.S.
Class: |
428/327; 427/226;
428/428; 428/429; 428/447; 428/448 |
Current CPC
Class: |
B05D
5/083 (20130101); B05D 7/54 (20130101); C03C
17/3405 (20130101); C03C 2217/42 (20130101); C03C
2217/47 (20130101); C03C 2217/475 (20130101); Y10T
428/31612 (20150401); Y10T 428/31663 (20150401); Y10T
428/254 (20150115) |
Current International
Class: |
B05D
5/08 (20060101); B05D 7/00 (20060101); C03C
17/34 (20060101); B32B 017/06 (); C09K
003/18 () |
Field of
Search: |
;428/327,428,429,447,448
;427/226 |
Foreign Patent Documents
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0513690 |
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Nov 1992 |
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EP |
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WO87/06161 |
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Oct 1987 |
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WO |
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Other References
Derwent Abstracts, AN-90-251019, JP-2 175 630, Jul. 6, 1990. .
Derwent Abstracts, AN 88-115470, JP-A-63 061 057, Mar. 17, 1988.
.
Chemical Abstracts, vol. 101, No. 4, Jul. 23, 1984, AN 27376,
JP-A-59 26 944, Feb. 13, 1984. .
Chemical Abstracts, vol. 104, No. 26, Jun. 30, 1986, AN 229299,
JP-A-61 40 845, Feb. 27, 1986..
|
Primary Examiner: Nakarani; D. S.
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier,
& Neustadt
Claims
What is claimed is:
1. A surface-treated substrate consisting essentially of a
substrate having at least two treated surface layers wherein the
first layer constituting the outermost layer among the treated
surface layers is a layer formed by treating with a treating agent
containing a compound (I) capable of forming a surface having a
contact angle of at least 70.degree. against water, and the second
layer constituting an underlayer in contact with the outermost
layer is a film layer of a heat resistant polymer formed by
treating with a treating agent containing a compound (II) capable
of forming a film of a heat resistant polymer and fine particles
having an average particle size of from 1 to 1,000 nm of a polymer,
to form a film and heating the film to thermally decompose the fine
particles of a polymer.
2. The substrate according to claim 1, wherein the substrate is
made of a transparent material.
3. The substrate according to claim 1, wherein the substrate is
made of glass.
4. The substrate according to claim 1, wherein the substrate is a
part of a transportation equipment.
5. The substrate according to claim 1, wherein the substrate is a
part of a building material of a building decoration.
6. The substrate according to claim 1, wherein the substrate is a
substrate having at least one film selected from the group
consisting of an antistatic film, a transparent electrically
conductive film, an electromagnetic wave shielding film, an
ultraviolet absorbing film, a heat ray absorbing film and a heat
ray reflecting film.
7. The substrate according to claim 1, wherein the compound (I) is
a reactive silane compound having at least one silicon atom having
an isocyanate group and/or a hydrolyzable group bonded thereto and
at least one hydrophobic group.
8. The substrate according to claim 7, wherein the hydrophobic
group is a polyfluoroorganic group and/or a C.sub.7 -C.sub.20 long
chain hydrocarbon group.
9. The substrate according to claim 8, wherein the
polyfluoroorganic group is an organic group having a C.sub.3-21
perfluoroalkyl moiety or a C.sub.2-16 perfluoroalkylene moiety, and
the long chain hydrocarbon group is a hydrocarbon group having a
C.sub.7-30 alkyl moiety or a C.sub.7-16 alkylene moiety.
10. The substrate according to claim 1, wherein the compound (I) is
at least one reactive silane compound of the following formula (A),
(B) or (C) wherein at least one organic group is a hydrophobic
group:
wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 which are
independent of one another, is hydrogen, a hydroxyl group, an amino
group or a C.sub.1-30 organic group, Y is a bivalent organic group,
Z is an isocyanate group and/or a hydrolyzable group, each of a and
b which are independent of each other, is an integer of 0, 1 or 2,
provided 0.ltoreq.a+b.ltoreq.2, and each of c and d which are
independent of each other, is an integer of 0, 1 or 2, provided
0.ltoreq.c+d.ltoreq.2,
wherein each of R.sup.5, R.sup.6 and R.sup.7 which are independent
of one another, is hydrogen, a hydroxyl group, an amino group or a
C.sub.1-30 organic group, provided that at least one of R.sup.5,
R.sup.6 R.sup.7, and is an organic group, Z is an isocyanate group
and/or a hydrolyzable group, and each of e, g and h which are
independent of one another, is an integer of 0, 1 or 2, provided
1.ltoreq.e+g+h.ltoreq.3,
wherein each of R.sup.8 to R.sup.13 which are independent of one
another, is hydrogen, a hydroxyl group, an amino group or a
C.sub.1-30 organic group, provided that at least one of R.sup.8 to
R.sup.13 is an organic group, Z is an isocyanate group and/or a
hydrolyzable group, each of i and j which are independent of each
other, is an integer of 0, 1 or 2, provided 1.ltoreq.i+j.ltoreq.3,
each of k and m which are independent of each other, is an integer
of 0, 1 or 2, provided 0.ltoreq.k+m.ltoreq.2, each of p and q which
are independent of each other, is an integer of 0, 1 or 2, provided
1.ltoreq.p+q.ltoreq.3, provided i+j+k+m+p+q.ltoreq.7, and n is an
integer of 0.ltoreq.n representing the number of repeating
units.
11. The substrate according to claim 10, wherein the hydrophobic
group is a polyfluoroorganic group and/or a C.sub.7 -C.sub.20 long
chain hydrocarbon group.
12. The substrate according to claim 11, wherein the
polyfluoroorganic group is an organic group having a C.sub.3-21
perfluoroalkyl moiety or a C.sub.2-16 perfluoroalkylene moiety, and
the long chain hydrocarbon group is a hydrocarbon group having a
C.sub.7-30 alkyl moiety or a C.sub.7-16 alkylene moiety.
13. The substrate according to claim 1, wherein the compound (II)
is a reactive silane compound having an isocyanate group and/or a
hydrolyzable group.
14. The substrate according to claim 1, wherein the compound (II)
is a tetraisocyanate silane and/or a tetraalkoxysilane.
15. The substrate according to claim 1, wherein the treating agent
for forming the second layer contains fine particles of a metal
and/or a metal oxide.
16. The substrate according to claim 1, made by a process which
comprises treating the surface of a substrate with a treating agent
containing a compound (II) capable of forming a film of a heat
resistant polymer and fine particles having an average particle
size of from 1 to 1,000 nm of a polymer, to form a film, heating
the film to thermally decompose the fine particles of a polymer to
form a film layer of a heat resistant polymer, and then treating
the surface of the film layer of a heat resistant polymer with a
treating agent containing a compound (I) capable of forming a
surface having a contact angle of at least 70.degree. against
water.
Description
TITLE OF THE INVENTION
1. Field of the Invention
The present invention relates to a substrate having a surface on
which water drops scarcely attach or from which attached water
drops can easily be removed.
2. Description of the Prior Art
Various substrates or various substrates having treated surface
layers are used in various fields, and adverse effects brought
about by water to the surface of such substrates are
problematic.
For example, in transportation equipments such as electric cars,
automobiles, ships or aircrafts, the surface of an exterior part
such as an outer panel, a window glass, a mirror or a display
surface material, an interior part such as an instrument panel, or
other articles, is desired to be always clean. If rain drops, dusts
or soils are attached, or moisture is condensed by an influence of
the temperature or humidity in air, on the surface of an article in
a transportation equipment, the outer appearance will be impaired.
If such is a surface which is directly visually observed or a
surface which is directly touched by a person, it may give an
unpleasant feeling or may create a hygienic problem. Further, such
may bring about a deterioration of the inherent function which the
article for a transportation instrument has. Especially in a case
where the article for the transportation equipment is an article
for which transparency or see-through property is required (such as
a window glass or a mirror), a deterioration of the transparency or
see-through property may mean that the purpose intended by the
article can not be attained, and may cause a serious accident.
A means to remove water drops (such as removal by wiping off or by
means of a wiper) may sometimes impart fine scratch marks on the
surface. Further, such scratch marks may sometimes be widened by
foreign particles accompanying water drops. Furthermore, it is well
known that when moisture is attached to a glass surface, glass
components are likely to elute into the moisture, whereby the
surface will be eroded, thus leading to so-called scorching. If the
surface is strongly polished or abraded to remove this scorching, a
fine roughness is likely to form. At the see-through portion made
of glass having substantial scorching or a fine roughness on its
surface, its basic function is lowered, and scattering of light on
its surface is substantial, whereby it tends to be difficult to
secure the field of view, and consequently there will be a problem
in securing the safety.
Further, moisture is likely to give a hazardous influence to the
surface of an article for a transportation instrument and to
promote damages, soiling, yellowing or corrosion. Otherwise, it may
induce a change in the electrical characteristics, the mechanical
properties or the optical properties of the article for a
transportation equipment. The adverse effects of this type brought
by water are problematic not only in the field of articles for
transportation equipments but also in various fields including
articles for building or building decoration or articles for
electric or electronic equipments.
Under these circumstances, it is desired to impart to the substrate
surface a characteristic such that water drops scarcely attach to
the substrate surface or attached water drops can easily be removed
(such a characteristic will hereinafter be referred to simply as
water repellency). Heretofore, to impart water repellency to a
surface, surface treating agents for direct application, such as a
surfactant and a silicone oil made of silicone wax or organo
polysiloxane, have been proposed.
However, such surface treating agents require pretreatment for
application in many cases, and have a problem that nonuniformity in
application is likely to occur. Further, the adhesive properties of
such treating agents to the substrates are rather poor, whereby the
durability of the water repellency has been inadequate, and the
application range has been rather limited.
The present invention has been accomplished in view of the above
problems. Namely, during the course of the research and study for a
treating agent which is capable of solving the drawbacks inherent
to the conventional treating agents, the present inventors have
found a treating agent which is applicable to various types of
substrates and which exhibits excellent water repellency, and have
confirmed that various substrates treated by such a treating agent
are suitable for use as substrates having water repellency,
particularly for transportation equipments or for building and
building decoration. The present invention has been accomplished on
the basis of these discoveries.
Accordingly, it is an object of the present invention to provide a
substrate having water repellency, whereby such an effect lasts
semipermanently with excellent abrasion resistance, chemical
resistance and weather resistance.
SUMMARY OF THE INVENTION
The above object can be attained by the present invention which
provides a surface-treated substrate consisting essentially of a
substrate having at least two treated surface layers wherein the
first layer constituting the outermost layer among the treated
surface layers is a layer formed by treating with a treating agent
containing a compound (I) capable of forming a surface having a
contact angle of at least 70.degree. against water, and the second
layer constituting an underlayer in contact with the outermost
layer is a thin film layer of a heat resistant polymer formed by
treating with a treating agent containing a compound (II) capable
of forming a thin film of a heat resistant polymer and fine
particles of a polymer, to form a thin film and heating the thin
film to thermally decompose the fine particles of a polymer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, the present invention will be described in detail with
reference to the preferred embodiments.
In the present invention, the compound (I) capable of forming a
surface having a contact angle of at least 70.degree. against water
(hereinafter referred to simply as the compound (I)) is a component
essential to provide the water repellency and the stain-proofing
property, and there is no particular restriction as to the
structure of the compound (I). However, the one having a reactive
group is preferred, when the adhesion to the second layer which
will be described hereinafter, is taken into consideration. Here,
the reactive group means e.g. a functional group such as a halogen
group, an alkoxy group, an acyloxy group, an alkoxy-substituted
alkoxy group, an aminoxy group, an amide group, an acid amide
group, a ketoxymate group, a hydroxyl group, a mercapto group, an
epoxy group, a glycidyl group, an unsaturated hydrocarbon group
such as a vinyl group or an allyl group, or a carboxyl group, or a
functional group having atoms capable of forming a hydrogen bond
(such as oxygen atoms or nitrogen atoms).
The compound (I) has at least one hydrophobic organic group, since
it is required to be a compound capable of forming a surface having
a contact angle of at least 70.degree. against water. As such a
hydrophobic organic group, a long chain hydrocarbon group or an
organic group having fluorine atoms is, for example, suitable.
As a result of extensive studies, it has been found that an
isocyanate silane compound having at least one isocyanate group
directly bonded to a silicon atom or a hydrolyzable silane compound
having at least one hydrolyzable group directly bonded to a silicon
atom, and having the above-mentioned hydrophobic organic group, is
particularly effective as the compound (I) in the present
invention.
Hereinafter, "the reactive silane compound" is used to generally
represent both "the hydrolyzable silane compound" and "the
isocyanate silane compound" as described below.
"The hydrolyzable silane compound" is a compound having at least
one hydrolyzable group bonded to a silicon atom.
"The isocyanate silane compound" is a compound having at least one
isocyanate group bonded to a silicon atom.
It is possible to consider that "the isocyanate group" is one type
of "the hydrolyzable group" (namely, the isocyanate group bonded to
a silicon atom may be regarded as one type of a hydrolyzable
group). However, in the present invention, the two are regarded as
being separate.
In the present invention, "the reactive silane group" will be used
as the general term representing both of "the isocyanate group" and
"the hydrolyzable group".
Preferred as a reactive silane compound is a compound having a
plurality of reactive silane groups. The compound (I) is preferably
a reactive silane compound as mentioned above. However, more
specifically, it is preferably at least one member selected from
the group consisting of a compound of the following formula (A)
(hereinafter sometimes referred to as compound A), a compound of
the following formula (B) (hereinafter sometimes referred to as
compound B), and a compound of the following formula (C)
(hereinafter sometimes referred to as compound C):
wherein each of R.sup.1, R.sup.2, R.sup.3 R.sup.4 which are
independent of one another, is hydrogen, a hydroxyl group, an amino
group or a C.sub.1-30 organic group, Y is a bivalent organic group,
Z is a reactive silane group (i.e. an isocyanate group and/or a
hydrolyzable group), each of a and b which are independent of each
other, is an integer of 0, 1 or 2, provided 0.ltoreq.a+b.ltoreq.2,
and each of c and d which are independent of each other, is an
integer of 0, 1 or 2, provided 0.ltoreq.c+d.ltoreq.2,
wherein each of R.sup.5, R.sup.6 and R.sup.7 which are independent
of one another, is hydrogen, a hydroxyl group, an amino group or a
C.sub.1-30 organic group, provided that at least one of R.sup.5,
R.sup.6 and R.sup.7 is an organic group, Z is a reactive silane
group (i.e. an isocyanate group and/or a hydrolyzable group), and
each of e, g and h which are independent of one another, is an
integer of 0, 1 or 2, provided 1.ltoreq.e+g+h.ltoreq.3,
wherein each of R.sup.8 to R.sup.13 which are independent of one
another, is hydrogen, a hydroxyl group, an amino group or a
C.sub.1-30 organic group, provided that at least one of R.sup.8 to
R.sup.13 is an organic group, Z is an isocyanate group and/or a
hydrolyzable group, each of i and j which are independent of each
other, is an integer of 0, 1 or 2, provided 1.ltoreq.i+j.ltoreq.3,
each of k and m which are independent of each other, is an integer
of 0, 1 or 2, provided 0.ltoreq.k+m.ltoreq.2, each of p and q which
are independent of each other, is an integer of 0, 1 or 2, provided
1.ltoreq.p+q.ltoreq.3, provided i+j+k+m+p+q.ltoreq.7, and n is an
integer of 0.ltoreq.n representing the number of repeating
units.
The compound (I) is preferably a reactive silane compound having at
least one hydrophobic organic group. Particularly, among compounds
A, B and C of the above chemical formulas, preferred is a compound
wherein at least one organic group is a hydrophobic group to obtain
excellent water repellency. In such a case, Z in the reactive
silane group may be an isocyanate group or a hydrolyzable group.
Both an isocyanate group and a hydrolyzable group may be present in
the compound (I).
The isocyanate group or the hydrolyzable group in the compound (I)
is a very important constituting unit to improve the adhesion with
various substrates.
Now, the compound (I) will be described in further detail.
When the compound (I) is an isocyanate silane compound, this
compound (hereinafter sometimes referred to as the compound
(I-NCO)) is required to be a compound capable of forming a surface
having a contact angle of at least 70.degree. against water.
Namely, the contact angle against water of the surface treated with
this compound (I-NCO) is required to be at least 70.degree.. The
compound (I-NCO) is believed to be chemically or physically bonded
to the layer to be treated. Since an isocyanate group is reactive,
the compound (I-NCO) is believed to be bonded to the surface of the
layer to be treated primarily by a chemical reaction. Namely, in
the bonded state, the isocyanate group is believed to be in a
modified form. For example, when the layer to be treated is formed
by a reactive silane as will be described hereinafter, an
isocyanate group is believed to react with a silanol group on the
surface of the layer to be treated, or a silanol group formed by
detachment of an isocyanate group is considered to react.
It is believed that due to the reactivity of the isocyanate group
or due to the effect of the silicon atom directly bonded to the
isocyanate group, the compound (I-NCO) exhibits excellent surface
properties such as water repellency, abrasion resistance, chemical
resistance and weather resistance.
Compounds A and B will form siloxane bonds by the reaction of
isocyanate groups (or hydrolyzable groups) among the respective
molecules of compounds A and B during the treatment, and therefore
the crosslinking degree and the density of the film obtained by the
treating agent of the present invention are high, which is believed
to be attributable to the high mechanical strength and chemical
stability of the film obtainable by the treating agent of the
present invention. On the other hand, compound C is a compound
having at least two siloxane bonds, and during the treatment, it
will form siloxane bonds by the reaction of isocyanate groups (or
hydrolyzable groups) to one another among the molecules of compound
C, and the crosslinking degree and the density of the film obtained
by the treating agent of the present invention will be remarkably
high, which is believed to be attributable to the high mechanical
strength and chemical stability of the film obtained by the
treating agent of the present invention. Further, with compound C,
it is conceivable to further increase the density and the
crosslinking degree of the film in this connection. Namely, the
number of repeating units may be increased (the number for n may be
increased) in compound C in the present invention. In such a case,
there is no particular limitation to the number for n, and n may be
optionally determined depending upon the particular purpose.
However, if n is too large, the working efficiency during the
treatment tends to be poor, and the practical operation efficiency
tends to be low, such being undesirable. The number for n is
preferably from 0 to 5. Particularly preferred is a case where
n=0.
Further, as described hereinafter, it is possible to further
improve such properties by selecting the organic group.
In the present invention, the number of isocyanate groups bonded to
one silicon atom is preferably at least two from the viewpoint of
the adhesion of the layer to be treated i.e. the layer formed on
the substrate surface (hereinafter referred to as a second
layer).
Further, in order to increase the adhesion to the underlayer by
means of compound C, it is conceivable to increase the number of
silicon atoms to which isocyanate groups are directly bonded in
compound C. This means that the number of repeating units is
increased in compound C in the present invention (i.e. the number
for n is increased). The number for n is not particularly limited
and may be optionally determined depending upon the particular
purpose. However, if n is too large, the working efficiency during
the treatment will be poor, and the practical operation efficiency
will be poor, such being undesirable. The number for n is
preferably from 0 to 5.
Next, when the compound (I) is a hydrolyzable silane compound, this
compound (hereinafter sometimes referred to as the compound (I-X))
is required to be a compound capable of forming a surface having a
contact angle of at least 70.degree. against water. Namely, the
contact angle against water of the surface treated with this
compound (I-X) is required to be at least 70.degree.. The compound
(I-X) is believed to be chemically or physically bonded to the
layer to be treated. Since the hydrolyzable group is reactive, the
compound (I-X) is believed to be bonded to the surface of the layer
to be treated primarily by a chemical reaction. Namely, in the
bonded state, the hydrolyzable group is believed to be in a
modified form.
The hydrolyzable group in this compound (I-X) is a group directly
bonded to a silicon atom. Such a hydrolyzable group includes, for
example, a halogen atom, an alkoxy group, an acyloxy group, an
alkoxy-substituted alkoxy group, an aminoxy group, an amide group,
an acid amide group and a ketoxymate group. Preferred is a
hydrolyzable group bonded to a silicon atom by means of an oxygen
atom, such as an alkoxy group, an alkoxy-substituted alkoxy group
or an acyl group. The number of carbon atoms of such a hydrolyzable
group is preferably at most 8, more preferably at most 4. Most
preferred is an alkoxy group having from 1 to 4 carbon atoms.
It is believed that due to the reactivity of this hydrolyzable
group or due to the effect of the silicon atom to which the
hydrolyzable group is directly bonded, the compound (I-X) exhibits
excellent surface properties such as water repellency, abrasion
resistance, chemical resistance and weather resistance. As
described hereinafter, these properties can further be improved by
properly selecting the organic groups. The number of hydrolyzable
groups bonded to one silicon atom is preferably at least two in
view of the bonding property to the second layer.
The compound (I-X) may be used by itself, but may also be used as a
partially hydrolyzed product obtained by hydrolysis. The partially
hydrolyzed product of the compound (I-X) is a compound having e.g.
a silanol group formed by partially hydrolyzing such a silane
compound in water or in an acidic aqueous solution, or a compound
obtained by condensation of at least two molecules by the reaction
of such silanol groups. As the acid, hydrochloric acid, acetic
acid, sulfuric acid, nitric acid, phosphoric acid or sulfonic acid
may, for example, be used.
These compounds (I-NCO) and (I-X) are preferably reactive silane
compounds A to C of the above described chemical formulas which are
capable of forming a surface having a contact angle of at least
70.degree. against water. Such preferable reactive silane compounds
A to C (hereinafter sometimes referred to as the compound (I-A),
(I-B) and (I-C), respectively), are compounds wherein R.sup.1 to
R.sup.13 are organic groups, and at least one of these organic
groups is a hydrophobic group, or Y is a hydrophobic group. All of
the organic groups may of course be hydrophobic groups. The number
of Z groups is preferably at least two per silicon atom. A
hydrophobic group is effective for the water repellency, and it is
believed that the larger the number of Z groups, the more firmly
the bond to the second layer becomes.
Each of R.sup.1 to R.sup.13 which are independent of one another,
is hydrogen, a hydroxyl group, an amino group or a C.sub.1-30
organic group. When each of R.sup.1 to R.sup.13 is an organic
group, such an organic group is preferably a hydrocarbon group such
as an alkyl group, an alkenyl group, a cycloalkyl group or an aryl
group, a halogenated hydrocarbon group such as a chloroalkyl group
or a polyfluoroalkyl group, a (halogenated)hydrocarbon group having
a hydroxyl group, an epoxy group, an amino group, a mercapto group,
a carboxy group or other functional group, or a
(halogenated)hydrocarbon group having an ester bond, an ether bond,
a thioether bond, an imino bond, an amide bond, a urethane bond or
other connecting bond in its carbon chain. Among them, the
hydrophobic group may be a long chain hydrocarbon group or a
polyfluoroalkyl group as described hereinafter. The long chain
hydrocarbon group is preferably an alkyl group or an alkenyl group
having from 7 to 20 carbon atoms. As an organic group which is not
a hydrophobic group, a lower alkyl group i.e. an alkyl group having
from 1 to 4 carbon atoms, is preferred.
More preferred as the compounds (I-A), (I-B) and (I-C) are reactive
silane compounds having at least two fluorine atoms. Namely, in the
case of the compound (I-A), a compound is preferred wherein Y is a
bivalent organic group having at least two fluorine atoms,
otherwise at least one of R.sup.1 to R.sup.4 is a monovalent
organic group having at least two fluorine atoms. Of course, both Y
and at least one of R.sup.1 to R.sup.4 may be organic groups having
at least two fluorine atoms.
In the case of the compound (I-B), a compound is preferred in which
at least one of R.sup.5 to R.sup.7 is a monovalent organic group
having at least two fluorine atoms. In such a case, the organic
group having no fluorine atom is preferably the above-mentioned
hydrocarbon group which is not a hydrophobic group. Further, the
organic group having at least two fluorine atoms is preferably
bonded to the silicon atom by means of a carbon atom having no
fluorine atom (such as a methylene group).
In the case of the compound (I-C), a compound is preferred in which
at least one of R.sup.8 to R.sup.13 is a monovalent organic group
having at least two fluorine atoms. In such a case, the organic
group having no fluorine atom is preferably the above-mentioned
hydrocarbon group which is not a hydrophobic group. Further, the
organic group having at least two fluorine atoms is preferably
bonded to the silicon atom by means of a carbon atom having no
fluorine atom (such as a methylene group).
When Y is a bivalent organic group having at least two fluorine
atoms, such a group is preferably a polyfluoroalkylene group, a
polyfluorooxalkylene group (the one wherein at least one ether bond
is present in the carbon chain of the alkylene group) or a
polyfluorothioxalkylene group (the one wherein at least one
thioether bond is present in the carbon chain of the alkylene
group). Particularly preferred is a bivalent organic group wherein
the portions bonded to silicon atoms at both ends are polymethylene
chains (particularly dimethylene groups) and the intermediate
portion is a perfluoroalkylene group or a perfluorooxalkylene
group. The number of carbon atoms of such Y is a preferably from 6
to 30, particularly from 6 to 16.
When Y is not a bivalent organic group having at least two fluorine
atoms, such a group is preferably an alkylene group, an oxalkylene
group or a thioxalkylene group. Its carbon number is preferably
from 2 to 30, particularly from 2 to 12. In the case of the
compound (I-A) wherein only Y is a hydrophobic group and Y has no
fluorine atom, the carbon number of such Y is preferably at least
7.
When any one of R.sup.1 to R.sup.13 is a monovalent organic group
having at least two fluorine atoms, such a group is preferably a
polyfluoroalkyl group, a polyfluorooxalkyl group or a
polyfluorothioxalkyl group, or an organic group wherein any one of
such groups and a hydrocarbon group such as an alkylene group are
bonded by an ester bond or other connecting bond as described above
(which organic group is bonded to a silicon atom at the other
terminal of the hydrocarbon group). The polyfluoroalkyl group or
the polyfluorooxalkyl group is preferably the one wherein the
terminal portions bonded to silicon atoms or the vicinities thereof
are alkylene groups (particularly dimethylene groups) and other
portion is a perfluoroalkylene group.
The perfluoro moiety of a monovalent organic group is preferably a
perfluoroalkyl group, a perfluorooxalkyl group or a
perfluorothioxalkyl group having at least 3 carbon atoms,
particularly a perfluoroalkyl group having from 3 to 16 carbon
atoms.
More specifically, particularly preferred is a polyfluoroalkyl
grcup having a perfluoroalkyl moiety, of the formula C.sub.n
F.sub.2n+1 C.sub.m H.sub.2m --wherein n is an integer of from 3 to
12, and m is an integer of from 2 to 4, or a perfluoroalkyl group
of the formula C.sub.n F.sub.2n+1 --wherein n is an integer of from
3 to 16.
Specific examples of the compounds (I-A), (I-B) and (I-C) will be
shown below. However, the compounds (I-A), (I-B) and (I-C) are not
restricted to such specific examples. In the following chemical
formulas, each of n and m is an integer of at least 1, R is an
alkyl group, etc., R.sub.f is a polyfluoroalkyl group, and R.sub.F
is a perfluoroalkyl group. In these chemical formulas, R preferably
has from 1 to 12 carbon atoms, and R.sub.f is preferably an ethyl
group having a perfluoroalkyl group at its terminal. Z is an
isocyanate group and/or a hydrolyzable group. ##STR1##
To the treating agent for forming the first layer in the present
invention, other compounds or additives may be added depending upon
the particular purpose. The additives, etc. may suitably be
selected taking the reactivity and compatibility with other
components into consideration. For example, it is possible to
incorporate super fine particles of various metals or metal oxides
such as silica, alumina, zirconia or titania, or various resins.
Further, a dye or pigment may also be added if tinting is required.
The amount of additives is usually at a level of from 0.01 to 20%
by weight based on the total amount of the compounds (I), and an
excessive addition is not advisable, since such will reduce the
water repellency or abrasion resistance of the present
invention.
Further, if electrical conductivity is required, it is possible to
add a material to provide an optional resistivity (such as tin
oxide, ITO or zinc oxide). The amount of such an additive may
suitably be determined depending upon the particular purpose.
The above composition may directly be coated on the second layer as
the coating object by a manual application method. Otherwise, it
may be used in the form of a solution prepared by dissolving or
diluting it with an organic solvent. The total amount of the
compounds (I) contained in the solution by means of such an organic
solvent is determined taking into consideration the formability of
the coating film (operation efficiency), the stability, the
thickness of the coating film and the economical aspect, and it is
usually within a range of from 0.1 to 30% by weight.
As the organic solvent, various organic solvents such as acetic
acid esters, aromatic hydrocarbons, halogenated hydrocarbons,
ketones, ethers or alcohols, may be employed. However, when the
compound A or B has an isocyanate group, a solvent having a
reactive functional group (such as a hydroxyl group) is
undesirable. Therefore, with respect to the compound (I-NCO),
alcohols are not desirable, but with respect to the compound (I-X),
there is no particular restriction. The diluting solvent may not be
limited to one type, and two or more solvents may be used in
combination as a mixture.
The compounds A to C are substances having low surface free energy.
A compound very limitedly present in a free state in the coating
film moves on the extreme surface layer to reduce the frictional
resistance on the surface, which is considered to be one of the
factors for excellent abrasion resistance.
For the treatment of the surface of the second layer, no special
pretreatment is required. A coating film may be formed by applying
the liquid containing the composition thus prepared, on the surface
by a usual method, such as brush coating, casting, spin coating,
dip coating or spray coating, followed by drying in air or in a
nitrogen stream.
Excellent properties can be obtained simply by drying in air.
However, for the purpose of increasing the drying rate, heating may
be employed without any problem. The heating temperature is
preferably at a level of from 50.degree. to 250.degree. C., and the
heating time is usually from 5 to 60 minutes. If the heating is
required, the heating temperature and time may be determined taking
into consideration the heat resistance of the substrate.
The thickness of the first layer formed by this surface treatment
is not particularly limited. However, it is preferred to be very
thin. A preferred film thickness is at most 2 .mu.m. The lower
limit is a single molecular layer thickness.
Now, the treating agent containing the compound (II) for forming a
thin film of a heat resistant polymer and fine particles of a
polymer, and the second layer formed by treatment therewith, will
be described.
In the present invention, as the materials for forming the second
layer, the compound (II) capable of forming a thin film of a heat
resistant polymer and fine particles of a polymer are used. The
second layer constituting an underlayer of the first layer serves
to improve the durability of the first layer remarkably, and it
also has an effect of improving the adhesion to the substrate. This
second layer is usually formed on the substrate surface. However,
there is no particular problem even when the substrate surface
already has a vapor-deposited film, a sputtered film or various
films formed by e.g. a wet system.
As such various films, an electrostatic film, a transparent
electrically conductive film, an electromagnetic wave shielding
film, an ultraviolet absorbing film, a heat ray absorbing film and
a heat ray reflecting film may, for example, be mentioned, and such
films may be used in a proper combination. The materials for
various films are not particularly limited, and films containing
metal oxides of e.g. Si, Zr, Ti, Zn, Al, Sn, Sb, Pb and Ta, may,
for example, be mentioned.
The compound (II) capable of forming a thin film of a heat
resistant polymer and the fine particles of a polymer to form the
second layer, are not particularly limited and may suitably be
selected depending upon the particular purpose. Polymer compounds
made of various commercially available materials may be used.
The fine particles of a polymer may, for example, be fine particles
of a polyethylene resin, a polypropylene resin, a polystyrene
resin, a polyacrylate resin, a polymethyl methacrylate resin, a
polyvinyl chloride resin, a polyvinyl alcohol resin, a
polycarbonate resin, a polyacetal resin, a polyester resin, a
polyamide resin, a polyimide resin, a fluorine resin, a phenol
resin, an epoxy resin and a silicone resin. As the material for the
fine particles of a polymer, at least one member selected from such
exemplified compounds, may be employed.
Among the above-mentioned materials for the fine particles of a
polymer, a thermoplastic resin such as a polystyrene resin or a
polymethyl methacrylate resin, is particularly preferred.
Further, when it is desired to provide roughness only on the
surface, it is advisable to employ fine polymer particles having a
low surface free energy. In such a case, a fluorine resin such as
PFA or PTFE is preferred as the material for the fine particles of
a polymer.
The average particle size of the fine particles of a polymer is not
particularly limited, but is preferably within a range of from 1 nm
to 1,000 nm from the viewpoint of the film strength. Particularly
when the transparency is of importance, the average particle size
is preferably at most 500 nm, more preferably at most 200 nm, for
the purpose of preventing scattering of light rays. The particle
size of the fine particles of a polymer is one of the factors for
controlling the degree of the surface roughness to be formed.
Namely, the larger the particle size of the fine particles of a
polymer, the larger the surface roughness. Namely, it becomes
possible to embed a larger amount of the upper layer material.
However, if the degree of the roughness is too much, the embedding
effect tends to be low, and the protection from abrasion tends to
be difficult, whereby the abrasion resistance will be low.
The molecular weight of the fine particles of a polymer is not
particularly limited so long as the above particle size is
satisfied, but the molecular weight is preferably from 10,000 to
1,000,000. If the molecular weight is too small, the fine particles
are likely to show interaction with the solvent and become
susceptible to the influence such as dissolution or swelling,
whereby it tends to be difficult to maintain the form of fine
particles of a polymer. On the other hand, if the molecular weight
is too large, it will be difficult to form fine particles.
Further, it is possible to control the degree of the depth of the
roughness by adjusting the particle size of the fine particles of a
polymer and the film thickness. For example, it is possible to form
deep roughness by increasing the film thickness or the particle
size of the fine particles of a polymer. Inversely, it is possible
to form shallow roughness by reducing the film thickness or by
using a reduced size of fine particles of a polymer in a thick
film.
The depth of roughness is preferably within a range of from 1 nm to
1,000 nm, more preferably from 10 nm to 50 nm, from the viewpoint
of the film strength.
On the other hand, the density of roughness can be controlled by
the shape of the fine particles of a polymer, the amount of
incorporation, etc.
The shape of the fine particles of a polymer is not particularly
limited, but is preferably spherical. Namely, in the case of
needle-like particles with a large aspect ratio, their presence in
the vicinity of the film surface tends to be random, and the
contour of the resulting roughness tends to be non-uniform, whereby
there will be a problem that the surface properties of the film are
not constant. Whereas, in the case of spherical particles, their
presence in the vicinity of the surface will be uniform, and
uniform roughness will be formed at the film surface, whereby the
surface properties of the film can be made constant.
Further, as compared with particles with a large aspect ratio,
spherical particles are advantageous also from the viewpoint of the
density of roughness. Accordingly, by using spherical particles, it
is possible to obtain a film having a larger surface area. The
larger surface area means an increase of reactive sites (functional
groups) which are reactive with the upper layer material, whereby
high densification of the upper layer material can be accomplished,
and the durability can be increased.
Further, even if the surface area of the underlayer is increased to
increase the reactive sites, with a conventional material, it has
been difficult to react it effectively (i.e. at a high probability)
with the reactive sites. Whereas, the compound (I) of the present
invention has a high reactivity and is capable of completely
reacting with the increased reactive sites, whereby high
densification of the upper layer material can certainly be
realized, and it is possible to attain the high water repellency,
chemical resistance, weather resistance and abrasion resistance of
the present invention.
Further, the shape of roughness serves to reduce the contact area
with an abrading object, and the roughness of the present invention
has a high degree of hardness, whereby the material embedded in the
roughness will be protected from abrasion, which is believed to be
attributable to the remarkably high abrasion resistance
accomplished by the present invention.
The proportion of the fine particles of a polymer to the total
amount of the compound (II) and the fine particles of a polymer, is
not particularly limited. Basically, the amount of the fine
particles of a polymer should be determined depending upon the
particular purpose. However, when it is desired to reduce the
density of the roughness, the amount may be small. Inversely, when
the density of the roughness is desired to be increased, the amount
may be large. To control the amount of the fine particles of a
polymer also means to control the amount of the material of the
first layer as its upper layer.
If the amount of the fine particles of a polymer is too large, the
mechanical strength of the coating film formed after the heat
decomposition tends to be low. Therefore, the amount is preferably
at most 80 wt %. On the other hand, if the amount is too low, the
effect of the addition of the fine particles of a polymer will
hardly be obtained. The amount is at least 5 wt %. Preferably, the
amount is from 5 to 50 wt %.
As mentioned above, the density of roughness can be controlled by
the amount and the shape of the fine particles of a polymer. The
density of roughness to be formed is preferably such that the
average distance between the centers of concaves or valleys is at
most 10 .mu.m, particularly preferably at most 1 .mu.m.
The shape of the resulting roughness can be controlled by the
film-forming method, the film thickness, the shape and diameter of
the fine particles of a polymer, etc., and may be determined
depending upon the particular purpose.
In the accompanying drawings, FIGS. 1 to 3 show cross sectional
diagrammatical views of cases where the fine particles of a polymer
are spherical. In the Figures, reference numeral 1 indicates fine
particles of a polymer, numeral 2 a thin film layer of a heat
resistant polymer, numeral 3 a substrate, and X an average distance
between the centers of the concaves or valleys.
As a preferred form, the fine particles of a polymer are embedded
to the film to some extent, followed by heat decomposition to form
roughness, as shown in FIGS. 2 and 3.
As shown in FIG. 3, if the volume of the fine particles of a
polymer embedded is at a certain level or more, raised portions
like craters will be formed along the spherical particles, which
contributes to the increase of the surface area, the reduction of
the contact area with an abrading object and the increase of the
effect for protecting the upper layer material and which is thus
effective.
The compound (II) capable of forming a thin film of a heat
resistant polymer may be a heat resistant polymer itself or a
compound which is capable of forming a heat resistance polymer by
e.g. polymerization at the time of the treatment. The heat
resistant polymer formed by this compound (II) is required to be a
material having a heat decomposition temperature higher than the
heat decomposition temperature of the fine particles of a polymer.
Particularly, it is preferably a material which undergo no chemical
or physical change at the time of the heat decomposition of the
fine particles of a polymer. The heat resistant polymer preferably
has a heat decomposition temperature higher by at least 50.degree.
C. than the heat decomposition temperature of the fine particles of
a polymer.
The compound (II) is the one capable of forming a thin film on the
surface of e.g. a substrate at the time of the treatment. For
example, the compound (II) dissolved or dispersed in the treating
agent is required to form a heat resistant polymer thin film by
removal of e.g. the solvent at the time of the treatment.
Specifically, a solution or a dispersion of a heat resistant
polymer itself or a compound capable of being cross-linked to form
a heat resistant polymer, is used. Further, a solution or a
dispersion of a compound capable of forming a heat resistant
polymer by hydrolysis, such as a tetraalkoxysilane or its partial
hydrolyzate, may also be used.
As the compound (II), the above-mentioned resin or the silicone
resin useful as the material for the fine particles of a polymer
may also be employed. The most preferred compound (II) is the
above-mentioned reactive silane compound and its partial
hydrolyzate. As such a reactive silane compound, a compound having
no hydrophobic group is preferred among compounds of the
above-mentioned formulas (A) and (B). Further, such a reactive
silane compound may have an organic group having a functional group
such as an epoxy group or an amino group.
The most preferred compound is a tetrafunctional reactive silane
compound. Such a compound is a compound of the above formula (B)
wherein e+g+h is 0, for example, a tetrafunctional reactive silane
compound such as a tetraalkoxysilane or a tetraisocyanate
silane.
The secondly preferred compound is a compound of the above formula
(A) wherein a+b=c+d=0. Y is preferably an alkylene group having at
most 6 carbon atoms and containing no fluorine atom. Further, a
compound of the above formula (B) which contains no hydrophobic
group, is also preferred. Likewise, a compound of the above formula
(A) which contains no hydrophobic group, may also be used. Further,
it is possible to employ the above compounds (I-A), (I-B) and (I-C)
which give thin films with water repellency relatively lower than
the compound (I) used for the first layer.
The compound (II) for forming the second layer is used preferably
as diluted with a solvent together with the fine particles of a
polymer and a binder, from the viewpoint of the operation
efficiency. As the solvent, the above-mentioned organic solvent or
the like may be used.
To the compound (II) for forming the second layer, other additives
may be incorporated. Specifically, such additives include, for
example, fillers such as fine particles of metal such as Sn, In,
Al, Zn, Zr, Ti, Sb, Pb, Ta and Si or metal oxides thereof, and
surfactants. Their proportions may suitably be from 0.01 to 20 wt %
based on the total weight of the compounds (II).
For the surface treatment of the substrate, no special pretreatment
is required. However, pretreatment may be conducted as the case
requires. For example, acid treatment with e.g. diluted
hydrofluoric acid or hydrochloric acid, alkali treatment with e.g.
an aqueous sodium hydroxide solution, or discharge treatment by
e.g. plasma irradiation, may be conducted.
Formulation of the second layer is not particularly limited.
However, the second layer may usually be formed by applying a
liquid composed of an organic solvent containing the compound (II)
thus prepared, by a usual treating method, such as brush coating,
casting, spin coating, dip coating or spray coating, followed by
drying in air or in a nitrogen stream under heating. By this heat
treatment, the fine particles of a polymer will undergo heat
decomposition, whereby a roughened surface will be formed.
Accordingly, the temperature for heating may be determined
depending upon the heat resistance of the spherical polymer
particles and the substrate. Usually, the treatment is conducted
within a range of from 300.degree. to 800.degree. C.
The heat decomposition of the fine particles of a polymer by the
heat treatment may not be complete, and an adequate effect of the
present invention can be obtained even by partial heat
decomposition, such that the fine particles of a polymer remain in
the interior of the thin film of a heat resistant polymer.
There is no particular restriction as to the thickness of the
second layer formed by this surface treatment. It may be very thin.
A preferred film thickness is at most 2 .mu.m like the case of the
first layer. A too much film thickness is undesirable from the
economical viewpoint and from the viewpoint of the scratch
resistance and the quality of appearance.
As mentioned above, the degree of roughness of the second layer
thus formed and the thicknesses of the respective layers can be
optionally controlled by e.g. the concentration of the composition
in the liquid containing the composition, the coating conditions,
the heating conditions, and the material, the amount and size of
the fine particles of a polymer.
The first layer of the present invention has a relatively low
refractive index, whereby low reflecting properties may be
imparted. If such an effect is desired, the thickness of the first
layer may be adjusted to a thickness where an optical interference
will occur. Theoretically, the thickness of the coating film may be
at least the thickness of a single molecular layer to obtain water
repellency. Taking an economical effect into consideration, the
thickness is preferably at most 2 .mu.m, as mentioned above.
There is no particular restriction as to the substrate to which the
present invention may be applied. For example, a metal, a plastic,
glass, ceramic or other inorganic materials, an organic material,
or a combination thereof (composite material, laminated material,
etc.) may be mentioned. Further, the surface of the substrate may,
of course, be the substrate surface itself, or may be the surface
of a material different from the substrate surface, such as the
coating surface of e.g. a coated metal plate, or the surface of a
surface-treated layer of e.g. surface-treated glass. With respect
to the shape of the substrate, it may not necessarily be a flat
plate, and it may have an optional shape depending upon the
particular purpose, such as the one having a curvature over the
entire surface or at a part thereof.
In the present invention, a particularly suitable substrate is a
substrate made of a transparent material such as glass, and a
suitable article is an article having such a substrate mounted to
utilize the transparency. Thus, the substrate of the present
invention is particularly suitable for articles for transportation
equipments and articles for buildings or building decorations.
Articles for transportation equipments may be exterior parts such
as outer plates, window glasses, mirrors and display panels, and
interior parts such as instrument panels, of the transportation
equipments such as electric cars, buses, trucks, automobiles, ships
or aircrafts, or parts or constituting elements to be used in other
transportation equipments.
For example, the articles for transportation equipments include
bodies, window glasses, pantagraphs, etc. of electric cars, bodies,
front glasses, side glasses, rear glasses, mirrors, bumpers, etc.
of automobiles, buses or trucks, bodies, window glasses, etc. of
ships, and bodies, window glasses, etc. of aircrafts.
Such an article may be composed solely of the surface-treated
substrate or may have the surface-treated substrate incorporated
therein. For example, the former may be a window glass for an
automobile, and the latter may be a back mirror for an automobile
in which a glass mirror is incorporated.
With such substrates or articles, water drops on the surface will
be repelled by the water repellency. Especially, in operation, due
to the interaction with the receiving wind pressure, water drops
rapidly move on the surface and will not remain as water drops,
whereby any adverse effect which may otherwise be induced by
moisture, can be eliminated. Especially in the application to a
see-through portion such as a window glass, it becomes easy to
secure a viewing field due to dissipation of water drops, thus
leading to improvement of the safety of a vehicle. Further, in an
environment where water drops usually freeze, no freezing takes
place, or even if freezing takes place, the frozen drops can
readily be defrosted. Further, there will be no substantial
deposition of water drops, whereby the number of periodical
cleaning operations can be reduced. Besides, the cleaning operation
is very easy, such being advantageous also for the protection of
good appearance.
Further, the articles for buildings or building decorations may be
articles to be attached to buildings or articles already attached
to buildings, or articles for buildings which are not attached to
buildings but which are used for the buildings, articles for
buildings such as furnitures or equipments, and base materials
(such as glass plates) constituting such articles.
Specifically, they include window glass plates, window glasses,
glass plates for roofs, various roofs including glass roofs, glass
plates for doors or doors having such glass plates installed, glass
plates for partitions, glass plates for green houses, or green
houses having such glass plates, transparent plastic plates to be
used instead of glass, the above-mentioned various articles for
buildings (window materials and roof materials) having such plastic
plates incorporated, wall materials made of ceramics, cement,
metals or other materials, mirrors, furnitures and display shelves
having such walls or mirrors, and glass for showcases.
Such an article may be made of the surface treated substrate alone
or may be the one having the surface treated substrate incorporated
therein. For example, the former may be a window glass plate, and
the latter may be a furniture in which a glass mirror is
incorporated.
With such a surface treated substrate, water drops which are
brought in contact with the surface are repelled due to the water
repellency and scarcely attach to the surface, or if attached, the
amount is small and the attached water drops can easily be removed.
Further, even in an environment where water drops usually freeze,
no freezing takes place, or even if freezing takes place, the
frozen drops can readily be defrosted. Further, there will be no
substantial deposition of water drops, whereby the number of
periodical cleaning operations can be reduced, and each cleaning
operation will be very easy, and such being advantageous also from
the viewpoint of the protection of good appearance.
Now, the present invention will be described in further detail with
reference to Examples. However, it should be understood that the
present invention is by no means restricted to such specific
Examples.
The methods for various evaluation tests on glass substrates having
coating films formed in the following Examples and Comparative
Examples and having water repellency and stain-proofing properties
are as follows. The water repellency after each test was evaluated
by measuring the contact angle.
1. Method for measuring the contact angle
The contact angle (.degree.) of a water drop having a size of 1 mm
in diameter was measured. Measurements were made at five different
points on the surface, and the contact angle was represented by the
average value.
2. Abrasion resistance test
Tester: Reprocation-type abrasion tester (manufactured by KNT).
Test condition: Flannel cloth, load: 1 kg, 10,000 times.
The abrasion test was carried out by the above test method, and the
water repellency after the test was evaluated.
3. Weather resistance test
A process comprising ultraviolet irradiation for 8 hours
(70.degree. C.) and humidity exposure for 4 hours (50.degree. C.)
is regarded as one cycle, and the weather resistance was conducted
by 200 cycles.
The weather resistance test was conducted by the above method, and
the water repellency after the test was evaluated.
4. Boiling test
A test sample was immersed in boiling water for one hour. The water
repellency after the test was evaluated.
5. Compounds used
(A) C.sub.9 F.sub.19 C.sub.2 H.sub.4 Si(OCH.sub.3).sub.3
(B) (CH.sub.3 O).sub.3 SiC.sub.2 H.sub.4 C.sub.6 F.sub.12 C.sub.2
H.sub.4 Si(OCH.sub.3).sub.3
(C) Si(OC.sub.2 H.sub.5).sub.4
(D) C.sub.8 F.sub.17 C.sub.2 H.sub.4 Si(NCO).sub.3
(E) C.sub.18 H.sub.37 Si(NCO).sub.3
(F) Si(NCO).sub.4
(G) (C.sub.8 F.sub.17 C.sub.2 H.sub.4)(NCO).sub.2 SiOSi(C.sub.8
F.sub.17 C.sub.2 H.sub.4)(NCO).sub.2
(H) (C.sub.8 F.sub.17 C.sub.2 H.sub.4)(NCO).sub.2
SiOSi(NCO).sub.3
PREPARATION EXAMPLE 1
Into a container equipped with a stirrer and a thermometer, 260.2 g
of hexylene glycol was introduced, and then 18.8 g of compound (C),
18.0 g of a 1 wt % hydrochloric acid aqueous solution, and 3.0 g of
fine particles of polystyrene having an average particle size of 70
nm were sequentially added thereto. The mixture was stirred at
30.degree. C. for 30 minutes and left to stand for one day to
obtain treating agent 1.
PREPARATION EXAMPLE 2
Into a container equipped with a stirrer and a thermometer, 260.2 g
of hexylene glycol was introduced, and then 18.8 g of compound (C),
and 18.0 g of a 1 wt % hydrochloric acid aqueous solution were
sequentially added thereto. The mixture was stirred at 30.degree.
C. for 30 minutes and then left to stand for one day to obtain
treating agent 2.
PREPARATION EXAMPLE 3
Into a container equipped with a stirrer and a thermometer, 803.9 g
of ethanol was introduced, and then 104.2 g of compound (C), 71.9 g
of a 1 wt % hydrochloric acid aqueous solution and 20.0 g of fine
particles of polymethyl methacrylate having an average particle
size of 150 nm were sequentially added thereto. The mixture was
stirred at 30.degree. C. for 30 minutes and then left to stand for
one day to obtain treating agent 3.
PREPARATION EXAMPLE 4
Into a container equipped with a stirrer and a thermometer, 246.8 g
of isopropyl alcohol was introduced, and then 2.6 g of compound
(A), 5.0 g of compound (B), 2.0 g of compound (C) and 2.2 g of a 1
wt % hydrochloric acid aqueous solution were sequentially added
thereto. The mixture was stirred at 30.degree. C. for 60 minutes
and then left to stand for 5 days to obtain treating agent 4.
PREPARATION EXAMPLE 5
Into a container equipped with a stirrer and a thermometer, 270.3 g
of isobutyl acetate was introduced, and then 27.0 g of compound
(D), 3.0 g of compound (E) and 0.6 g of compound (F) were
sequentially added thereto. The mixture was stirred at 25.degree.
C. for 10 minutes to obtain treating agent 5.
PREPARATION EXAMPLE 6
Into a container equipped with a stirrer and a thermometer, 834.8 g
of hexylene glycol was introduced, and then 40.0 g of a dispersion
of fine particles of polymethyl methacrylate having an average
particle size of 80 nm, 62.5 g of ethyl silicate 40 and 62.4 g of a
1 wt % hydrochloric acid aqueous solution were sequentially added
thereto. The mixture was stirred at 30.degree. C. for 30 minutes
and then left to stand for one day to obtain treating agent 6.
PREPARATION EXAMPLE 7
Into a three-necked flask equipped with a stirrer and a
thermometer, 1.0 g of compound (G) and 99.0 g of freon 225 were
added and stirred for one hour. While maintaining the temperature
of this solution at 25.degree. C., stirring was continued for one
day to obtain treating agent 7.
PREPARATION EXAMPLE 8
Into a three-necked flask equipped with a stirrer and a
thermometer, 1.0 g of compound (H) and 99.0 g of freon 225 were
added and stirred for one hour. While maintaining the temperature
of this solution at 25.degree. C., stirring was continued for one
day to obtain treating agent 8.
PREPARATION EXAMPLE 9
Into a three-necked flask equipped with a stirrer and a
thermometer, 3.0 g of compound (D) and 97.0 g of ethyl acetate were
added and stirred for one hour. While maintaining the temperature
of this solution at 25.degree. C., stirring was continued for one
day to obtain treating agent 9.
PREPARATION EXAMPLE 10
Into a container equipped with a stirrer and a thermometer, 834.8 g
of hexylene glycol were introduced, and then 40.0 g of a dispersion
of fine particles of polymethyl methacrylate having an average
particle size of 80 nm, 120.5 g of a dispersion of fine particles
of tin oxide sol having an average particle size of 5 nm, 62.5 g of
ethyl silicate 40 and 62.4 g of a 1 wt % hydrochloric acid aqueous
solution were sequentially added thereto. The mixture was stirred
at 30.degree. C. for 30 minutes and then left to stand for one day
to obtain treating agent 10.
EXAMPLE 1
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 1 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
600.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, this substrate was dipped in treating agent 4
and withdrawn therefrom at a rate of 6 cm/min, whereupon it was
subjected to heat treatment at 200.degree. C. for 30 minutes to
obtain a sample test piece. This sample test piece was evaluated,
and the results are shown in Table 1.
EXAMPLE 2
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 3 was coated by a spin coating method and
subjected to heat treatment in a muffle furnace at 650.degree. C.
for 10 minutes. After the heat treatment, the substrate was
withdrawn from the muffle furnace and cooled to room temperature.
Then, this substrate was dipped in treating agent 4 and withdrawn
at a rate of 6 cm/min, whereupon it was subjected to heat treatment
at 200.degree. C. for 30 minutes to obtain a sample test piece.
This sample test piece was evaluated, and the results are shown in
Table 1.
EXAMPLE 3
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 1 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
600.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, to this substrate, treating agent 5 was dropped
and coated in the same manner as waxing, followed by drying at room
temperature for 60 minutes to obtain a sample test piece. This
sample test piece was evaluated, and the results are shown in Table
1.
EXAMPLE 4
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 3 was coated by a dip coating method and
subjected to heat treatment in a muffle furnace at 650.degree. C.
for 10 minutes. After the heat treatment, the substrate was
withdrawn from the muffle furnace and cooled to room temperature.
Then, to this substrate, treating agent 5 was dropped and coated in
the same manner as waxing, followed by drying at room temperature
for 60 minutes to obtain a sample test piece. This sample test
piece was evaluated, and the results are shown in Table 1.
EXAMPLE 5
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 3 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
650.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, to this substrate, treating agent 7 was dropped
and coated in the same manner as waxing, followed by drying at room
temperature for 60 minutes to obtain a sample test piece. This
sample test piece was evaluated, and the results are shown in Table
1.
EXAMPLE 6
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 6 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
650.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, to this substrate, treating agent 8 was dropped
and coated in the same manner as waxing, followed by drying at room
temperature for 60 minutes to obtain a sample test piece. This
sample test piece was evaluated, and the results are shown in Table
1.
EXAMPLE 7
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 6 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
650.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, to this substrate, treating agent 9 was dropped
and coated in the same manner as waxing, followed by drying at room
temperature for 60 minutes to obtain a sample test piece. This
sample test piece was evaluated, and the results are shown in Table
1.
COMPARATIVE EXAMPLE 1
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 2 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
600.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, this substrate was dipped in treating agent 4
and withdrawn at a rate of 6 cm/min, whereupon it was subjected to
heat treatment at 200.degree. C. for 30 minutes to obtain a sample
test piece. This sample test piece was evaluated, and the results
are shown in Table 1.
COMPARATIVE EXAMPLE
A glass substrate previously polished by cerium oxide and cleaned,
was dipped in treating agent 4 and withdrawn at a rate of 6 cm/min,
whereupon it was subjected to heat treatment at 200.degree. C. for
30 minutes to obtain a sample test piece. This sample test piece
was evaluated, and the results are shown in Table 1.
TABLE 1 ______________________________________ Contact angle
(.degree.) Abrasion Weather Examples Initial Boiling resistance
resistance ______________________________________ Example 1 110 102
104 100 Example 2 110 104 102 102 Example 3 114 108 107 107 Example
4 115 108 108 106 Example 5 117 113 110 110 Example 6 117 112 111
110 Example 7 115 109 109 108 Comparative 110 77 30 88 Example 1
Comparative 114 82 54 48 Example 2
______________________________________
It was confirmed by Examples 1 to 7 that the glass products of the
present invention had excellent water repellency, adhesion,
abrasion resistance and weather resistance.
Further, it was confirmed that with the glass products having a
construction containing no fine particles of a polymer as an
essential component of the present invention (Comparative Example
1) and a construction having no underlayer (Comparative Example 2),
the adhesion, the abrasion resistance and the weather resistance
were inadequate.
EXAMPLE 8
The test piece prepared in Example 4 was dipped in the reagent as
identified in Table 2 for 24 hours, withdrawn and immediately
washed, and then the change in appearance and the water repellency
of this test piece were evaluated. The results are shown in Table
2.
TABLE 2 ______________________________________ Change in Contact
Reagent appearance angle (.degree.)
______________________________________ Methanol No change 112
Acetone No change 112 Toluene No change 112 Water No change 111 1%
sulfuric acid No change 112 aqueous solution 1% sodium hydroxide No
change 110 aqueous solution Commercial cleanser No change 110
Gasoline No change 112 ______________________________________
As is apparent from the above Table, it was confirmed that the
glass products of the present invention are excellent in the
chemical resistance.
EXAMPLE 9
Treatment of the surface of a laminated front glass for an
automobile was conducted in the same manner as in Example 5, and
the front glass thus treated was mounted on an automobile. Thus
automobile was subjected to a running test for 4 hours during day
time every day for one month, and the deposition of dust and stain
on the surface of the front glass, or in a rainy day, the
deposition of water, drops, was visually observed every day.
As a result, no deposition of dust or stain, or no formation of fur
due to deposition of water drops, was observed, or even when
observed, it was readily removed by gently wiping it off with a
tissue paper. Further, at the time of raining, water drops on the
surface were repelled and moved away swiftly by the interaction
with the wind pressure due to running, whereby the viewing field
was secured without using a wiper. Further, in a running test in an
environment (0.degree. C. to -5.degree. C.) where water drops
deposited on a non-treated laminated front glass would freeze, or
moisture in air would condense to form frost on a front glass, no
formation of frost on the front glass was observed.
In a severer low temperature environment (-10.degree. C. to
-15.degree. C.), formation of frost on the front glass was
observed, but defrosting was quick, and there was a substantial
difference as compared with the non-treated front glass.
EXAMPLE 10
The running test was conducted in the same manner as in Example 9
except that the method of Example 5 was changed to the method of
Example 7, whereby the same effects as in Example 9 were
confirmed.
EXAMPLE 11
The running test was conducted in the same manner as in Example 9
except that the laminated front glass in Example 9 was changed to a
side glass or a rear glass, whereby the same effects as in Example
9 were confirmed.
EXAMPLE 12
The running test was conducted in the same manner as in Example 9
except that the laminated front glass in Example 9 was changed to a
side mirror, whereby the same effects as in Example 9 was
confirmed.
EXAMPLE 13
Coating on the surface of a window glass for building was conducted
in the same manner as in Example 9 to form a coating film. The
window glass thus obtained was mounted on a house. The deposition
of dust and stain on the surface of this window glass, or in a
rainy day, the deposition of water drops, was visually observed
every day.
As a result, no deposition of dust or stain, or no formation of fur
due to deposition of water drops, was observed, or even when
observed, it was readily be removed by gently wiping it off with a
tissue paper. Further, at the time of rain, water drops on the
surface were repelled and fell off, and especially when strong wind
blew, water drops were readily moved off by the interaction with
the wind pressure, whereby the viewing field was secured. Further,
in a test under an environment (0.degree. C. to -5.degree. C.)
where water drops deposited on a non-treated window glass would
freeze, or moisture in air would condense to form frost on a window
glass, no formation of frost on the window glass was observed.
In a severer low temperature environment (-10.degree. C. to
-15.degree. C.), formation of frost on the window glass was
observed, but the defrosting was quick, and there was a substantial
difference as compared with the non-treated window glass.
EXAMPLE 14
On a glass substrate previously polished by cerium oxide and
cleaned, treating agent 10 was coated by a flexographic printing
method and subjected to heat treatment in a muffle furnace at
650.degree. C. for 10 minutes. After the heat treatment, the
substrate was withdrawn from the muffle furnace and cooled to room
temperature. Then, to this substrate, treating agent 7 was dropped
and coated in the same manner as waxing, followed by drying at room
temperature for 60 minutes to obtain a sample test piece. The
surface resistance of this sample test piece was 3.times.10.sup.8
.OMEGA./.smallcircle. as measured by MCP-TESTER, manufactured by
Mitsubishi Petrochemical Co., Ltd. Further, the same sample was
evaluated, and the results are shown in Table 3.
TABLE 3 ______________________________________ Contact angle
(.degree.) Abrasion Weather Examples Initial Boiling resistance
resistance ______________________________________ Example 14 114
109 104 101 ______________________________________
Thus, it was confirmed possible to incorporate an electrically
conductive material to the treating agent of the present invention
and to impart electrical conductivity by such incorporation of an
electrically conductive material. Further, it was confirmed that
even when the electrically conductive material was incorporated,
the glass product of the present invention had excellent water
repellency, adhesion, abrasion resistance and weather
resistance.
In Example 14, an electrically conductive material is exemplified
as the additive. However, the glass product of the present
invention provides the equal performance even when the electrically
conductive material is substituted by other additives.
The substrate of the present invention or an article provided
therewith exhibits excellent effects as is apparent from the
Examples. Namely:
1. It is excellent in the water repellency and free from deposition
of dust, stain or water drops, or free from formation of fur due to
such deposition. Even if observed, such deposition can readily be
removed, whereby adverse effects resulting from water can be
prevented, and cleaning operation can be simplified.
2. It is excellent in maintaining the water repellency and is
capable of maintaining such a condition semi-permanently.
3. It is excellent in chemical resistance and can be applied at a
region along sea coast or at a region where sea water is directly
in contact. Thus, it is applicable in a wide range of fields.
4. The water repellency is most suitable for use in the field of
transportation equipments and in the field of buildings and
building decorations.
The above effects can not be expected with conventional materials,
and the present invention is expected to be applied in an area
where the conventional materials could not be practically used.
* * * * *